Earth’s Cryosphere, 2010, Vol. XIV, No. 1, p. 32-40

WINTER TEMPERATURE CONDITIONS OF LAPTEV SEA REGION DURING THE LAST 50 THOUSANDS YEARS IN THE ISOTOPIC RECORDS OF ICE WEDGES

A.Yu. Dereviagin, A.B. Chizhov, H. Meyer*

Lomonosov Moscow State University, Department of Geology, 119992, Moscow, Vorobyovy Gory, Russia, dereviag@online.ru
*Alfred Wegener Institute of Polar and Marine Research, Potsdam, Telegrafenberg A43, 14473, Germany

The winter air temperature reconstruction has been carried out on the base of oxygen isotopic analysis (δ¹⁸О) of about 1600 ice wedges samples and radiocarbon data of ice and enclosed sediments. The frequency of different winter temperature conditions from very cold (mean winter temperature from –36 to –32 °С) to warm (from –20 to –16 °С) has been estimated during the last 50 ka. The Holocene and modern rises in mean winter temperatures correspondingly for 5 and 3 °С occur due to the increase (more than 4 times) in the contribution of relatively warm (mean winter temperature more than –28 °С) winters. The fast progress of Holocene warming in the period from 11 to 3 ka as well as the brief rises in winter temperature in 38 and 13 ka BP (5 °С) are marked out. The possible correlation between isotopic records of the Greenland ice cores and the important paleoclimatic events in the Laptev Sea region are discussed.

Key words: Ice-wedges, oxygen isotopic analysis, radiocarbon dating, winter air temperature, Late Pleistocene, Holocene.

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